manti tao. we are told he was trying to lead the fighting irish to winning season. in the middle of it, his grandmother and girlfriend died within hours of one another. the story captured the hearts of college football fans across america. but today, it's unraveling, as we learn that the girlfriend who supposedly died of leukemia never even existed. listen to him describe his girlfriend he called kirk >> she was the most beautiful girl, not because of her physical beauty by the beauty of her and what she is. a person i turn to. she was fighting leukemia and various things she found time to serve someone else. >> kimberly: he says is the victim of a hoax after learning the give wasn't real. notre dame says he's victim of a hoax. >> our investigators through their work discovered online chatter among the perpetrators that was the ultimate proof of this. the single most trusting human being i have ever met will never trust in the same way in his life. that is an incredible tragedy. >> kimberly: you know the fighting irish has his back. what is the truth? what do we thi